.container-ad{
    margin-top:12px;
    padding: 0;
    font-size: 0;
}
.container-ad .ad1{
    display: inline-block;
    height:75px;
    width:700px;
}
.container-ad .ad1 img{
    width:100%;
    height: 100%;
}

.container-ad .ad2{
    float: right;
    width: 280px;
    height: 75px;
}
.container-ad .ad2 img{
    width:100%;
    height: 100%;
}
/* 广告3的调整 */
.ad3 {
    height:75px;
    width:700px;
}
.ad3 img{
    width:100%;
    height: 100%;
}